4 * Copyright 2003, Jouni Malinen <jkmaline@cc.hut.fi>
5 * Copyright 2002-2005, Instant802 Networks, Inc.
6 * Copyright 2005-2006, Devicescape Software, Inc.
7 * Copyright 2006-2007 Jiri Benc <jbenc@suse.cz>
8 * Copyright 2007, Michael Wu <flamingice@sourmilk.net>
9 * Copyright 2007-2010, Intel Corporation
11 * This program is free software; you can redistribute it and/or modify
12 * it under the terms of the GNU General Public License version 2 as
13 * published by the Free Software Foundation.
16 #include <linux/ieee80211.h>
17 #include <linux/slab.h>
18 #include <linux/export.h>
19 #include <net/mac80211.h>
20 #include "ieee80211_i.h"
21 #include "driver-ops.h"
25 * DOC: TX A-MPDU aggregation
27 * Aggregation on the TX side requires setting the hardware flag
28 * %IEEE80211_HW_AMPDU_AGGREGATION. The driver will then be handed
29 * packets with a flag indicating A-MPDU aggregation. The driver
30 * or device is responsible for actually aggregating the frames,
31 * as well as deciding how many and which to aggregate.
33 * When TX aggregation is started by some subsystem (usually the rate
34 * control algorithm would be appropriate) by calling the
35 * ieee80211_start_tx_ba_session() function, the driver will be
36 * notified via its @ampdu_action function, with the
37 * %IEEE80211_AMPDU_TX_START action.
39 * In response to that, the driver is later required to call the
40 * ieee80211_start_tx_ba_cb_irqsafe() function, which will really
41 * start the aggregation session after the peer has also responded.
42 * If the peer responds negatively, the session will be stopped
43 * again right away. Note that it is possible for the aggregation
44 * session to be stopped before the driver has indicated that it
45 * is done setting it up, in which case it must not indicate the
48 * Also note that, since we also need to wait for a response from
49 * the peer, the driver is notified of the completion of the
50 * handshake by the %IEEE80211_AMPDU_TX_OPERATIONAL action to the
51 * @ampdu_action callback.
53 * Similarly, when the aggregation session is stopped by the peer
54 * or something calling ieee80211_stop_tx_ba_session(), the driver's
55 * @ampdu_action function will be called with the action
56 * %IEEE80211_AMPDU_TX_STOP. In this case, the call must not fail,
57 * and the driver must later call ieee80211_stop_tx_ba_cb_irqsafe().
60 static void ieee80211_send_addba_request(struct ieee80211_sub_if_data *sdata,
61 const u8 *da, u16 tid,
62 u8 dialog_token, u16 start_seq_num,
63 u16 agg_size, u16 timeout)
65 struct ieee80211_local *local = sdata->local;
67 struct ieee80211_mgmt *mgmt;
70 skb = dev_alloc_skb(sizeof(*mgmt) + local->hw.extra_tx_headroom);
75 skb_reserve(skb, local->hw.extra_tx_headroom);
76 mgmt = (struct ieee80211_mgmt *) skb_put(skb, 24);
78 memcpy(mgmt->da, da, ETH_ALEN);
79 memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN);
80 if (sdata->vif.type == NL80211_IFTYPE_AP ||
81 sdata->vif.type == NL80211_IFTYPE_AP_VLAN)
82 memcpy(mgmt->bssid, sdata->vif.addr, ETH_ALEN);
83 else if (sdata->vif.type == NL80211_IFTYPE_STATION)
84 memcpy(mgmt->bssid, sdata->u.mgd.bssid, ETH_ALEN);
86 mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
87 IEEE80211_STYPE_ACTION);
89 skb_put(skb, 1 + sizeof(mgmt->u.action.u.addba_req));
91 mgmt->u.action.category = WLAN_CATEGORY_BACK;
92 mgmt->u.action.u.addba_req.action_code = WLAN_ACTION_ADDBA_REQ;
94 mgmt->u.action.u.addba_req.dialog_token = dialog_token;
95 capab = (u16)(1 << 1); /* bit 1 aggregation policy */
96 capab |= (u16)(tid << 2); /* bit 5:2 TID number */
97 capab |= (u16)(agg_size << 6); /* bit 15:6 max size of aggergation */
99 mgmt->u.action.u.addba_req.capab = cpu_to_le16(capab);
101 mgmt->u.action.u.addba_req.timeout = cpu_to_le16(timeout);
102 mgmt->u.action.u.addba_req.start_seq_num =
103 cpu_to_le16(start_seq_num << 4);
105 ieee80211_tx_skb(sdata, skb);
108 void ieee80211_send_bar(struct ieee80211_vif *vif, u8 *ra, u16 tid, u16 ssn)
110 struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
111 struct ieee80211_local *local = sdata->local;
113 struct ieee80211_bar *bar;
116 skb = dev_alloc_skb(sizeof(*bar) + local->hw.extra_tx_headroom);
120 skb_reserve(skb, local->hw.extra_tx_headroom);
121 bar = (struct ieee80211_bar *)skb_put(skb, sizeof(*bar));
122 memset(bar, 0, sizeof(*bar));
123 bar->frame_control = cpu_to_le16(IEEE80211_FTYPE_CTL |
124 IEEE80211_STYPE_BACK_REQ);
125 memcpy(bar->ra, ra, ETH_ALEN);
126 memcpy(bar->ta, sdata->vif.addr, ETH_ALEN);
127 bar_control |= (u16)IEEE80211_BAR_CTRL_ACK_POLICY_NORMAL;
128 bar_control |= (u16)IEEE80211_BAR_CTRL_CBMTID_COMPRESSED_BA;
129 bar_control |= (u16)(tid << IEEE80211_BAR_CTRL_TID_INFO_SHIFT);
130 bar->control = cpu_to_le16(bar_control);
131 bar->start_seq_num = cpu_to_le16(ssn);
133 IEEE80211_SKB_CB(skb)->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT;
134 ieee80211_tx_skb(sdata, skb);
136 EXPORT_SYMBOL(ieee80211_send_bar);
138 void ieee80211_assign_tid_tx(struct sta_info *sta, int tid,
139 struct tid_ampdu_tx *tid_tx)
141 lockdep_assert_held(&sta->ampdu_mlme.mtx);
142 lockdep_assert_held(&sta->lock);
143 rcu_assign_pointer(sta->ampdu_mlme.tid_tx[tid], tid_tx);
146 int ___ieee80211_stop_tx_ba_session(struct sta_info *sta, u16 tid,
147 enum ieee80211_back_parties initiator,
150 struct ieee80211_local *local = sta->local;
151 struct tid_ampdu_tx *tid_tx;
154 lockdep_assert_held(&sta->ampdu_mlme.mtx);
156 spin_lock_bh(&sta->lock);
158 tid_tx = rcu_dereference_protected_tid_tx(sta, tid);
160 spin_unlock_bh(&sta->lock);
164 /* if we're already stopping ignore any new requests to stop */
165 if (test_bit(HT_AGG_STATE_STOPPING, &tid_tx->state)) {
166 spin_unlock_bh(&sta->lock);
170 if (test_bit(HT_AGG_STATE_WANT_START, &tid_tx->state)) {
171 /* not even started yet! */
172 ieee80211_assign_tid_tx(sta, tid, NULL);
173 spin_unlock_bh(&sta->lock);
174 kfree_rcu(tid_tx, rcu_head);
178 set_bit(HT_AGG_STATE_STOPPING, &tid_tx->state);
180 spin_unlock_bh(&sta->lock);
182 #ifdef CONFIG_MAC80211_HT_DEBUG
183 printk(KERN_DEBUG "Tx BA session stop requested for %pM tid %u\n",
185 #endif /* CONFIG_MAC80211_HT_DEBUG */
187 del_timer_sync(&tid_tx->addba_resp_timer);
190 * After this packets are no longer handed right through
191 * to the driver but are put onto tid_tx->pending instead,
192 * with locking to ensure proper access.
194 clear_bit(HT_AGG_STATE_OPERATIONAL, &tid_tx->state);
197 * There might be a few packets being processed right now (on
198 * another CPU) that have already gotten past the aggregation
199 * check when it was still OPERATIONAL and consequently have
200 * IEEE80211_TX_CTL_AMPDU set. In that case, this code might
201 * call into the driver at the same time or even before the
202 * TX paths calls into it, which could confuse the driver.
204 * Wait for all currently running TX paths to finish before
205 * telling the driver. New packets will not go through since
206 * the aggregation session is no longer OPERATIONAL.
210 tid_tx->stop_initiator = initiator;
211 tid_tx->tx_stop = tx;
213 ret = drv_ampdu_action(local, sta->sdata,
214 IEEE80211_AMPDU_TX_STOP,
215 &sta->sta, tid, NULL, 0);
217 /* HW shall not deny going back to legacy */
220 * We may have pending packets get stuck in this case...
221 * Not bothering with a workaround for now.
229 * After sending add Block Ack request we activated a timer until
230 * add Block Ack response will arrive from the recipient.
231 * If this timer expires sta_addba_resp_timer_expired will be executed.
233 static void sta_addba_resp_timer_expired(unsigned long data)
235 /* not an elegant detour, but there is no choice as the timer passes
236 * only one argument, and both sta_info and TID are needed, so init
237 * flow in sta_info_create gives the TID as data, while the timer_to_id
238 * array gives the sta through container_of */
239 u16 tid = *(u8 *)data;
240 struct sta_info *sta = container_of((void *)data,
241 struct sta_info, timer_to_tid[tid]);
242 struct tid_ampdu_tx *tid_tx;
244 /* check if the TID waits for addBA response */
246 tid_tx = rcu_dereference(sta->ampdu_mlme.tid_tx[tid]);
248 test_bit(HT_AGG_STATE_RESPONSE_RECEIVED, &tid_tx->state)) {
250 #ifdef CONFIG_MAC80211_HT_DEBUG
251 printk(KERN_DEBUG "timer expired on tid %d but we are not "
252 "(or no longer) expecting addBA response there\n",
258 #ifdef CONFIG_MAC80211_HT_DEBUG
259 printk(KERN_DEBUG "addBA response timer expired on tid %d\n", tid);
262 ieee80211_stop_tx_ba_session(&sta->sta, tid);
266 static inline int ieee80211_ac_from_tid(int tid)
268 return ieee802_1d_to_ac[tid & 7];
272 * When multiple aggregation sessions on multiple stations
273 * are being created/destroyed simultaneously, we need to
274 * refcount the global queue stop caused by that in order
275 * to not get into a situation where one of the aggregation
276 * setup or teardown re-enables queues before the other is
277 * ready to handle that.
279 * These two functions take care of this issue by keeping
280 * a global "agg_queue_stop" refcount.
282 static void __acquires(agg_queue)
283 ieee80211_stop_queue_agg(struct ieee80211_local *local, int tid)
285 int queue = ieee80211_ac_from_tid(tid);
287 if (atomic_inc_return(&local->agg_queue_stop[queue]) == 1)
288 ieee80211_stop_queue_by_reason(
290 IEEE80211_QUEUE_STOP_REASON_AGGREGATION);
291 __acquire(agg_queue);
294 static void __releases(agg_queue)
295 ieee80211_wake_queue_agg(struct ieee80211_local *local, int tid)
297 int queue = ieee80211_ac_from_tid(tid);
299 if (atomic_dec_return(&local->agg_queue_stop[queue]) == 0)
300 ieee80211_wake_queue_by_reason(
302 IEEE80211_QUEUE_STOP_REASON_AGGREGATION);
303 __release(agg_queue);
306 void ieee80211_tx_ba_session_handle_start(struct sta_info *sta, int tid)
308 struct tid_ampdu_tx *tid_tx;
309 struct ieee80211_local *local = sta->local;
310 struct ieee80211_sub_if_data *sdata = sta->sdata;
314 tid_tx = rcu_dereference_protected_tid_tx(sta, tid);
317 * While we're asking the driver about the aggregation,
318 * stop the AC queue so that we don't have to worry
319 * about frames that came in while we were doing that,
320 * which would require us to put them to the AC pending
321 * afterwards which just makes the code more complex.
323 ieee80211_stop_queue_agg(local, tid);
325 clear_bit(HT_AGG_STATE_WANT_START, &tid_tx->state);
328 * make sure no packets are being processed to get
329 * valid starting sequence number
333 start_seq_num = sta->tid_seq[tid] >> 4;
335 ret = drv_ampdu_action(local, sdata, IEEE80211_AMPDU_TX_START,
336 &sta->sta, tid, &start_seq_num, 0);
338 #ifdef CONFIG_MAC80211_HT_DEBUG
339 printk(KERN_DEBUG "BA request denied - HW unavailable for"
342 spin_lock_bh(&sta->lock);
343 ieee80211_assign_tid_tx(sta, tid, NULL);
344 spin_unlock_bh(&sta->lock);
346 ieee80211_wake_queue_agg(local, tid);
347 kfree_rcu(tid_tx, rcu_head);
351 /* we can take packets again now */
352 ieee80211_wake_queue_agg(local, tid);
354 /* activate the timer for the recipient's addBA response */
355 mod_timer(&tid_tx->addba_resp_timer, jiffies + ADDBA_RESP_INTERVAL);
356 #ifdef CONFIG_MAC80211_HT_DEBUG
357 printk(KERN_DEBUG "activated addBA response timer on tid %d\n", tid);
360 spin_lock_bh(&sta->lock);
361 sta->ampdu_mlme.addba_req_num[tid]++;
362 spin_unlock_bh(&sta->lock);
364 /* send AddBA request */
365 ieee80211_send_addba_request(sdata, sta->sta.addr, tid,
366 tid_tx->dialog_token, start_seq_num,
367 local->hw.max_tx_aggregation_subframes,
371 int ieee80211_start_tx_ba_session(struct ieee80211_sta *pubsta, u16 tid,
374 struct sta_info *sta = container_of(pubsta, struct sta_info, sta);
375 struct ieee80211_sub_if_data *sdata = sta->sdata;
376 struct ieee80211_local *local = sdata->local;
377 struct tid_ampdu_tx *tid_tx;
380 trace_api_start_tx_ba_session(pubsta, tid);
382 if (WARN_ON(!local->ops->ampdu_action))
385 if ((tid >= STA_TID_NUM) ||
386 !(local->hw.flags & IEEE80211_HW_AMPDU_AGGREGATION) ||
387 (local->hw.flags & IEEE80211_HW_TX_AMPDU_SETUP_IN_HW))
390 #ifdef CONFIG_MAC80211_HT_DEBUG
391 printk(KERN_DEBUG "Open BA session requested for %pM tid %u\n",
393 #endif /* CONFIG_MAC80211_HT_DEBUG */
396 * The aggregation code is not prepared to handle
397 * anything but STA/AP due to the BSSID handling.
398 * IBSS could work in the code but isn't supported
399 * by drivers or the standard.
401 if (sdata->vif.type != NL80211_IFTYPE_STATION &&
402 sdata->vif.type != NL80211_IFTYPE_AP_VLAN &&
403 sdata->vif.type != NL80211_IFTYPE_AP)
406 if (test_sta_flag(sta, WLAN_STA_BLOCK_BA)) {
407 #ifdef CONFIG_MAC80211_HT_DEBUG
408 printk(KERN_DEBUG "BA sessions blocked. "
409 "Denying BA session request\n");
414 spin_lock_bh(&sta->lock);
416 /* we have tried too many times, receiver does not want A-MPDU */
417 if (sta->ampdu_mlme.addba_req_num[tid] > HT_AGG_MAX_RETRIES) {
422 tid_tx = rcu_dereference_protected_tid_tx(sta, tid);
423 /* check if the TID is not in aggregation flow already */
424 if (tid_tx || sta->ampdu_mlme.tid_start_tx[tid]) {
425 #ifdef CONFIG_MAC80211_HT_DEBUG
426 printk(KERN_DEBUG "BA request denied - session is not "
427 "idle on tid %u\n", tid);
428 #endif /* CONFIG_MAC80211_HT_DEBUG */
433 /* prepare A-MPDU MLME for Tx aggregation */
434 tid_tx = kzalloc(sizeof(struct tid_ampdu_tx), GFP_ATOMIC);
440 skb_queue_head_init(&tid_tx->pending);
441 __set_bit(HT_AGG_STATE_WANT_START, &tid_tx->state);
443 tid_tx->timeout = timeout;
446 tid_tx->addba_resp_timer.function = sta_addba_resp_timer_expired;
447 tid_tx->addba_resp_timer.data = (unsigned long)&sta->timer_to_tid[tid];
448 init_timer(&tid_tx->addba_resp_timer);
450 /* assign a dialog token */
451 sta->ampdu_mlme.dialog_token_allocator++;
452 tid_tx->dialog_token = sta->ampdu_mlme.dialog_token_allocator;
455 * Finally, assign it to the start array; the work item will
456 * collect it and move it to the normal array.
458 sta->ampdu_mlme.tid_start_tx[tid] = tid_tx;
460 ieee80211_queue_work(&local->hw, &sta->ampdu_mlme.work);
462 /* this flow continues off the work */
464 spin_unlock_bh(&sta->lock);
467 EXPORT_SYMBOL(ieee80211_start_tx_ba_session);
470 * splice packets from the STA's pending to the local pending,
471 * requires a call to ieee80211_agg_splice_finish later
473 static void __acquires(agg_queue)
474 ieee80211_agg_splice_packets(struct ieee80211_local *local,
475 struct tid_ampdu_tx *tid_tx, u16 tid)
477 int queue = ieee80211_ac_from_tid(tid);
480 ieee80211_stop_queue_agg(local, tid);
482 if (WARN(!tid_tx, "TID %d gone but expected when splicing aggregates"
483 " from the pending queue\n", tid))
486 if (!skb_queue_empty(&tid_tx->pending)) {
487 spin_lock_irqsave(&local->queue_stop_reason_lock, flags);
488 /* copy over remaining packets */
489 skb_queue_splice_tail_init(&tid_tx->pending,
490 &local->pending[queue]);
491 spin_unlock_irqrestore(&local->queue_stop_reason_lock, flags);
495 static void __releases(agg_queue)
496 ieee80211_agg_splice_finish(struct ieee80211_local *local, u16 tid)
498 ieee80211_wake_queue_agg(local, tid);
501 static void ieee80211_agg_tx_operational(struct ieee80211_local *local,
502 struct sta_info *sta, u16 tid)
504 struct tid_ampdu_tx *tid_tx;
506 lockdep_assert_held(&sta->ampdu_mlme.mtx);
508 tid_tx = rcu_dereference_protected_tid_tx(sta, tid);
510 #ifdef CONFIG_MAC80211_HT_DEBUG
511 printk(KERN_DEBUG "Aggregation is on for tid %d\n", tid);
514 drv_ampdu_action(local, sta->sdata,
515 IEEE80211_AMPDU_TX_OPERATIONAL,
516 &sta->sta, tid, NULL, tid_tx->buf_size);
519 * synchronize with TX path, while splicing the TX path
520 * should block so it won't put more packets onto pending.
522 spin_lock_bh(&sta->lock);
524 ieee80211_agg_splice_packets(local, tid_tx, tid);
526 * Now mark as operational. This will be visible
527 * in the TX path, and lets it go lock-free in
530 set_bit(HT_AGG_STATE_OPERATIONAL, &tid_tx->state);
531 ieee80211_agg_splice_finish(local, tid);
533 spin_unlock_bh(&sta->lock);
536 void ieee80211_start_tx_ba_cb(struct ieee80211_vif *vif, u8 *ra, u16 tid)
538 struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
539 struct ieee80211_local *local = sdata->local;
540 struct sta_info *sta;
541 struct tid_ampdu_tx *tid_tx;
543 trace_api_start_tx_ba_cb(sdata, ra, tid);
545 if (tid >= STA_TID_NUM) {
546 #ifdef CONFIG_MAC80211_HT_DEBUG
547 printk(KERN_DEBUG "Bad TID value: tid = %d (>= %d)\n",
553 mutex_lock(&local->sta_mtx);
554 sta = sta_info_get(sdata, ra);
556 mutex_unlock(&local->sta_mtx);
557 #ifdef CONFIG_MAC80211_HT_DEBUG
558 printk(KERN_DEBUG "Could not find station: %pM\n", ra);
563 mutex_lock(&sta->ampdu_mlme.mtx);
564 tid_tx = rcu_dereference_protected_tid_tx(sta, tid);
566 if (WARN_ON(!tid_tx)) {
567 #ifdef CONFIG_MAC80211_HT_DEBUG
568 printk(KERN_DEBUG "addBA was not requested!\n");
573 if (WARN_ON(test_and_set_bit(HT_AGG_STATE_DRV_READY, &tid_tx->state)))
576 if (test_bit(HT_AGG_STATE_RESPONSE_RECEIVED, &tid_tx->state))
577 ieee80211_agg_tx_operational(local, sta, tid);
580 mutex_unlock(&sta->ampdu_mlme.mtx);
581 mutex_unlock(&local->sta_mtx);
584 void ieee80211_start_tx_ba_cb_irqsafe(struct ieee80211_vif *vif,
585 const u8 *ra, u16 tid)
587 struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
588 struct ieee80211_local *local = sdata->local;
589 struct ieee80211_ra_tid *ra_tid;
590 struct sk_buff *skb = dev_alloc_skb(0);
595 ra_tid = (struct ieee80211_ra_tid *) &skb->cb;
596 memcpy(&ra_tid->ra, ra, ETH_ALEN);
599 skb->pkt_type = IEEE80211_SDATA_QUEUE_AGG_START;
600 skb_queue_tail(&sdata->skb_queue, skb);
601 ieee80211_queue_work(&local->hw, &sdata->work);
603 EXPORT_SYMBOL(ieee80211_start_tx_ba_cb_irqsafe);
605 int __ieee80211_stop_tx_ba_session(struct sta_info *sta, u16 tid,
606 enum ieee80211_back_parties initiator,
611 mutex_lock(&sta->ampdu_mlme.mtx);
613 ret = ___ieee80211_stop_tx_ba_session(sta, tid, initiator, tx);
615 mutex_unlock(&sta->ampdu_mlme.mtx);
620 int ieee80211_stop_tx_ba_session(struct ieee80211_sta *pubsta, u16 tid)
622 struct sta_info *sta = container_of(pubsta, struct sta_info, sta);
623 struct ieee80211_sub_if_data *sdata = sta->sdata;
624 struct ieee80211_local *local = sdata->local;
625 struct tid_ampdu_tx *tid_tx;
628 trace_api_stop_tx_ba_session(pubsta, tid);
630 if (!local->ops->ampdu_action)
633 if (tid >= STA_TID_NUM)
636 spin_lock_bh(&sta->lock);
637 tid_tx = rcu_dereference_protected_tid_tx(sta, tid);
644 if (test_bit(HT_AGG_STATE_STOPPING, &tid_tx->state)) {
645 /* already in progress stopping it */
650 set_bit(HT_AGG_STATE_WANT_STOP, &tid_tx->state);
651 ieee80211_queue_work(&local->hw, &sta->ampdu_mlme.work);
654 spin_unlock_bh(&sta->lock);
657 EXPORT_SYMBOL(ieee80211_stop_tx_ba_session);
659 void ieee80211_stop_tx_ba_cb(struct ieee80211_vif *vif, u8 *ra, u8 tid)
661 struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
662 struct ieee80211_local *local = sdata->local;
663 struct sta_info *sta;
664 struct tid_ampdu_tx *tid_tx;
666 trace_api_stop_tx_ba_cb(sdata, ra, tid);
668 if (tid >= STA_TID_NUM) {
669 #ifdef CONFIG_MAC80211_HT_DEBUG
670 printk(KERN_DEBUG "Bad TID value: tid = %d (>= %d)\n",
676 #ifdef CONFIG_MAC80211_HT_DEBUG
677 printk(KERN_DEBUG "Stopping Tx BA session for %pM tid %d\n",
679 #endif /* CONFIG_MAC80211_HT_DEBUG */
681 mutex_lock(&local->sta_mtx);
683 sta = sta_info_get(sdata, ra);
685 #ifdef CONFIG_MAC80211_HT_DEBUG
686 printk(KERN_DEBUG "Could not find station: %pM\n", ra);
691 mutex_lock(&sta->ampdu_mlme.mtx);
692 spin_lock_bh(&sta->lock);
693 tid_tx = rcu_dereference_protected_tid_tx(sta, tid);
695 if (!tid_tx || !test_bit(HT_AGG_STATE_STOPPING, &tid_tx->state)) {
696 #ifdef CONFIG_MAC80211_HT_DEBUG
697 printk(KERN_DEBUG "unexpected callback to A-MPDU stop\n");
702 if (tid_tx->stop_initiator == WLAN_BACK_INITIATOR && tid_tx->tx_stop)
703 ieee80211_send_delba(sta->sdata, ra, tid,
704 WLAN_BACK_INITIATOR, WLAN_REASON_QSTA_NOT_USE);
707 * When we get here, the TX path will not be lockless any more wrt.
708 * aggregation, since the OPERATIONAL bit has long been cleared.
709 * Thus it will block on getting the lock, if it occurs. So if we
710 * stop the queue now, we will not get any more packets, and any
711 * that might be being processed will wait for us here, thereby
712 * guaranteeing that no packets go to the tid_tx pending queue any
716 ieee80211_agg_splice_packets(local, tid_tx, tid);
718 /* future packets must not find the tid_tx struct any more */
719 ieee80211_assign_tid_tx(sta, tid, NULL);
721 ieee80211_agg_splice_finish(local, tid);
723 kfree_rcu(tid_tx, rcu_head);
726 spin_unlock_bh(&sta->lock);
727 mutex_unlock(&sta->ampdu_mlme.mtx);
729 mutex_unlock(&local->sta_mtx);
732 void ieee80211_stop_tx_ba_cb_irqsafe(struct ieee80211_vif *vif,
733 const u8 *ra, u16 tid)
735 struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
736 struct ieee80211_local *local = sdata->local;
737 struct ieee80211_ra_tid *ra_tid;
738 struct sk_buff *skb = dev_alloc_skb(0);
743 ra_tid = (struct ieee80211_ra_tid *) &skb->cb;
744 memcpy(&ra_tid->ra, ra, ETH_ALEN);
747 skb->pkt_type = IEEE80211_SDATA_QUEUE_AGG_STOP;
748 skb_queue_tail(&sdata->skb_queue, skb);
749 ieee80211_queue_work(&local->hw, &sdata->work);
751 EXPORT_SYMBOL(ieee80211_stop_tx_ba_cb_irqsafe);
754 void ieee80211_process_addba_resp(struct ieee80211_local *local,
755 struct sta_info *sta,
756 struct ieee80211_mgmt *mgmt,
759 struct tid_ampdu_tx *tid_tx;
763 capab = le16_to_cpu(mgmt->u.action.u.addba_resp.capab);
764 tid = (capab & IEEE80211_ADDBA_PARAM_TID_MASK) >> 2;
765 buf_size = (capab & IEEE80211_ADDBA_PARAM_BUF_SIZE_MASK) >> 6;
767 mutex_lock(&sta->ampdu_mlme.mtx);
769 tid_tx = rcu_dereference_protected_tid_tx(sta, tid);
773 if (mgmt->u.action.u.addba_resp.dialog_token != tid_tx->dialog_token) {
774 #ifdef CONFIG_MAC80211_HT_DEBUG
775 printk(KERN_DEBUG "wrong addBA response token, tid %d\n", tid);
780 del_timer_sync(&tid_tx->addba_resp_timer);
782 #ifdef CONFIG_MAC80211_HT_DEBUG
783 printk(KERN_DEBUG "switched off addBA timer for tid %d\n", tid);
787 * addba_resp_timer may have fired before we got here, and
788 * caused WANT_STOP to be set. If the stop then was already
789 * processed further, STOPPING might be set.
791 if (test_bit(HT_AGG_STATE_WANT_STOP, &tid_tx->state) ||
792 test_bit(HT_AGG_STATE_STOPPING, &tid_tx->state)) {
793 #ifdef CONFIG_MAC80211_HT_DEBUG
795 "got addBA resp for tid %d but we already gave up\n",
802 * IEEE 802.11-2007 7.3.1.14:
803 * In an ADDBA Response frame, when the Status Code field
804 * is set to 0, the Buffer Size subfield is set to a value
807 if (le16_to_cpu(mgmt->u.action.u.addba_resp.status)
808 == WLAN_STATUS_SUCCESS && buf_size) {
809 if (test_and_set_bit(HT_AGG_STATE_RESPONSE_RECEIVED,
811 /* ignore duplicate response */
815 tid_tx->buf_size = buf_size;
817 if (test_bit(HT_AGG_STATE_DRV_READY, &tid_tx->state))
818 ieee80211_agg_tx_operational(local, sta, tid);
820 sta->ampdu_mlme.addba_req_num[tid] = 0;
822 ___ieee80211_stop_tx_ba_session(sta, tid, WLAN_BACK_INITIATOR,
827 mutex_unlock(&sta->ampdu_mlme.mtx);